From my experience, any product that genuinely solves a problem or feels a need at the right time is your best bet.
Before picking a product, ask yourself the following:
-will this fulfill a need or solve a problem?
-is it economically feasible?
-will it get delivered in record time? (because people don't like to wait);
Answering yes to one, two, or all of the above is a good enough reason to start promoting a product.
